CXCL13 and myeloid sarcoma: Probably the most widely-documented chemokine in the pathophysiology of MS is chemokine (C-X-C motif) ligand 13 (CXCL13), a “B-cell attracting chemokine” (Ragheb et al., 2011) known to play an essential role in the recruitment and activation of immune cells to inflammatory foci in Pan et al. (2022).